Justin Bieber’s new album ‘Believe’ is beautifully sung and deftly adds a Euro-house beat to the teen idol’s usual R&B mix.

At this point in his whirlwind career, Justin Bieber’s singing ranks among the least important drivers of his fame. More significant in a minute-to-minute sense are his freshly upswept hair (a kind of post-emo pompadour), his exclamatory Twitter feed (“FRANCE!! i see u. thank u!!”) and the many, many photographs depicting his and girlfriend Selena Gomez’s support of the Southern California fast-food industry (these kids love their Chick-fil-A). We’re talking the nuts and bolts, in other words, of 21st century teen idoldom — the everyday texture of a life lived under the social-media microscope.

Yet if Bieber’s voice has gotten relatively short shrift over the two years since he released “My World 2.0,” the Canadian-born pop star’s new sophomore full-length serves as a gentle correction: For all its cutting-edge production and grown-up talk of “swag, swag, swag,” “Believe” feels designed primarily to showcase his increasing vocal ability; it might be the year’s most beautifully sung recording.

As befits a young man who turned 18 in March, Bieber’s voice has deepened from the mall-rat squeak captured in early tunes like “One Less Lonely Girl” and the adorably aspirational “Bigger,” which urged a girlfriend to believe in him “like a fairy tale / Put a tooth under your pillowcase.” (The innocent bedtime fantasy was a recurring trope on Bieber’s 2009 debut EP, “My World”: “I know they said belief in love is a dream that can’t be real,” he acknowledged in “Favorite Girl,” “So, girl, let’s write a fairy tale and show ‘em how we feel.”)

That inevitable downward tendency, though, hasn’t thickened Bieber’s appealingly lightweight tone in new songs such as “Boyfriend” and “Catching Feelings”; the latter, especially, demonstrates how nimbly he can navigate a melody that sounds borrowed from teen-years Michael Jackson.

Jackson’s early work is an obvious lodestar on “Believe,” as is “Justified,” the solo debut that Justin Timberlake released in 2002 following his stint with the hugely successful boy band ‘N Sync. In “Die In Your Arms,” Rodney Jerkins — one of Bieber’s key producers here, along with Adam Messinger and Nasri — samples Jackson’s “We’ve Got a Good Thing Going,” from 1972′s “Ben” album; “Take You” evokes the clipped funk of Timberlake’s “Like I Love You.”

But although it’s rooted in the blue-eyed R&B that Bieber grew up channeling (and eventually attracted attention with on YouTube), “Believe” also takes on the bludgeoning Euro-house groove that’s lately made stars out of such non-singing DJs as David Guetta and Swedish House Mafia. For many pop vocalists the dance-music environment isn’t a terribly friendly workplace — too much forward momentum, not enough space to fill with sound. At best it can reduce a singer to his or her most baseline characteristics, as in Guetta’s “Night of Your Life,” which features Jennifer Hudson in what might be described as a guest-firehose role.

Bieber somehow eludes those enforced limitations: Even in cuts as cyborg-sleek as “All Around the World” and the Max Martin-produced “Beauty and a Beat” he keeps the focus tight, emphasizing his inflection. It’s difficult to think of a recent four-on-the-floor record with more melisma than this one. Sometimes Bieber uses that ample vocal technique to make a point about his pop-star prowess: “I don’t know about me, but I know about you,” he sings over a skeletal hip-hop beat in “Boyfriend,” “So say hello to falsetto in three, two…” In the unlikely event that you haven’t heard “Boyfriend” — it’s inside the top 10 on iTunes, Spotify and Billboard’s Hot 100 — you can figure out what happens next.

At other points on “Believe,” though, Bieber summons an expressive vulnerability that feels more or less unmatched among his current peers. In “Right Here,” a duet with Drake, Bieber transfers a child’s elemental need for a parent to a lover’s dependence on another.

In these songs Bieber seems perfectly comfortable inhabiting his producers’ high-tech soundscapes; he’s young enough to have had computers define his existence. But “Believe” also strikes an unexpectedly lifelike note. It reminds you that Bieber Fever is a communicable disease, one passed from human to human.

Justin Bieber“Believe”(RBMG/Schoolboy/Island)Three and a half stars (Out of four)